Data Center (DC) is developing from standardization, virtualization to automation. DC based on cloud computing is a target in the near future. With standardization as the foundation, virtualization is the technology to implement automated and cloud based DCs.
There may be many advantages for the digitalization of the DC. For example, resource utilization may be improved by integrating or sharing physical resources. Research shows that utilization of most of the DCs in the world is between 15% and 20%. By employing the technologies of standardization and virtualization, resource utilization of 50% to 60% may be implemented. An energy efficient, green DC may be implemented by employing virtualization technologies. For example, costs for physical devices, cables, physical space, electric power, and refrigeration may be reduced. Meanwhile, rapid deployment and re-deployment of resources may be implemented to meet service demands.
Thus, it can be seen that virtualization technologies are a focus in the development of the DC. For a basic network, virtualization technologies may be divided into two categories. In a first category, multiple physical devices are integrated into a logical device to simply network structure, which may be referred to as N:1 virtualization, such as stacking technologies. In a second category, a set of physical network is divided into multiple logical networks isolated from each other, or one physical device is divided into multiple virtual devices, which may be referred to as 1:N virtualization.